Importance of non-additive effects on chemisorption and catalysis: Part II. Activation of hydrogen by copper in its ground and excited atomic states

Abstract In Part I of this series, a multibody analysis of the adsorption energy was proposed as a measure of the delocalization of adsorbate-metal catalyst interactions. Furthermore, the idea of describing the catalyst as a third body promoting the breaking of chemical bonds in dissociative adsorption processes was presented and exemplified in the Li + H 2 reaction. Now we choose another metal atom: copper, in order to take advantage of recent studies on the Cu + H 2 reaction, where the copper atom was taken to be in its ground ( 2 S) state and in the excited states Cu( 2 P) and Cu( 2 D). We shall here show that detailed knowledge of the three-body non-additive contributions to the copper-hydrogen interaction energy once more provides us with a valuable guide to understanding why and how the diverse states of Cu behave so differently in the capture and cleavage of the H 2 molecule.